What Is a Terrarium? Bring Your Home to Life With an Indoor Garden

What Is a Terrarium?

A Terrarium is essentially an enclosed environment for growing plants. Usually made of clear glass or plastic, terrariums come in all shapes and sizes, from mini-terrariums for individual miniature plants to windowsill size planters right up to large terrariums where you can create an extensive habitat. Once established a terrarium requires only minimal maintenance, as this clever plant system recycles moisture through the process of evaporation and condensation, therefore may not require watering for months at a time!

The sustainability of a Terrarium makes them ideal for non-green-fingered individuals, and especially handy for those who usually forget to water their houseplants! Complete beginners can also buy inexpensive ready-made kits (which also make great gifts) and come with all the required materials and instructions for setting up a fully functioning terrarium. Terrariums can also make great educational projects for kids, as they help budding young scientists understand the water cycle, plant growth, and different habitats.

Indoor Gardening Trend

In the early 19th century London-based Dr Nathaniel Ward wrote letters to many gardener’s magazines of his successful attempts at growing rare and delicate plants, mostly British ferns, in small glasses, rather like miniature indoor greenhouses. Following this fern cases or “Wardian cases” as they became known not only started appearing in elegant drawing rooms, and also made it possible for living plants to be transported worldwide. Ferns later became the most popular of all house and garden plants. The fashion for these cases declined towards the end of the 19th century and today you would be very lucky indeed to come across an original Wardian case, even in an antique shop.

However, a modern-day version is now gaining popularity and finding favour with a new generation of indoor gardeners! Known as a Terrarium, Plant Case or Indoor Garden, they can vary from a modest jar housing a single plant to purpose-built miniature greenhouses. Today’s indoor gardener is not restricted to growing just ferns, although many of these do thrive enclosed in glass, given enough warmth, tropical and sub-tropical foliage plants of any kind can be used. Flowering plants will also do well so long as you can reach in easily to remove dead flowers. African Violets (Saintpaulias) and their relatives are cheap and make easy terrarium subjects, while many of the smaller orchids will also thrive.

How Do Terrariums Work?

Terrariums are an ideal means of growing plants, keeping them away from the hot, dry atmosphere of today’s centrally heated homes. Inside a terrarium, a humid microclimate is built up within the confines of the glass which, combined with adequate heat, suits more tender houseplants whose natural habitat would be a steamy tropical bushland. The community within a terrarium is almost self-supporting, it’s physical ingredients being cycled and recycled by the plant life. Water in the potting mixture is given off as vapour from their leaves. This condenses as droplets on the glass walls and roof, to run back down into the soil; the atmosphere inside also remains in balance, the plants absorbing oxygen at night and giving off carbon dioxide, reversing the process in the daylight.

How to Plant Your Terrarium

Always make sure that the terrarium is clean before planting, and select plants to suit its shape and size, ensuring that they all like the same growing conditions. A drainage layer of agricultural charcoal or a mix of charcoal and gravel is essential, About an inch (3cm) in small terrariums to 2 inches in larger containers makes a good foundation. Then add twice that depth of moist potting soil which is not too rich in fertilizer. Water should then be added sparingly. When planting. allow room for the plants to grow, otherwise, it will become overcrowded very quickly and you be able to see the individual plants. The potting mix should always remain slightly moist. With closed terrariums, there should be slight condensation on the inside. If condensation is excessive leave the lid off for a few days to let it dry out. If there is no condensation, water very carefully with a fine spray. Place your glass garden in good light but not in direct sunlight as it will get too warm.

Choosing the Right Plants for Your Terrarium

Terrariums are a great way to bring greenery into your indoor environment. However, not all plants are suited to terrariums as the high humidity would cause some to decay. The best plants for closed terrariums are those native to woodlands and marshy places, Artillery Ferns such as Maidenhair, Mosses of almost every sort, and for splashes of colour flowering perennial houseplants such as Cyclamen, Grape Hyacinths and African Violets.

Succulents and Cacti for Open Terrariums

If you would like to plant Succulents and Cacti in a terrarium, you will need to ensure that the glass container has an opening at the top and that you provide sandy soil with a low moisture content. Succulents also require plenty of light, preferably natural light, to grow.

What Is so Great about Terrariums?

Like an oasis in the desert, a tiny garden growing inside a glass container is irresistibly fascinating. A terrarium invites you to create your own scene, imitating nature on a miniature scale. Indoor gardening can be challenging but is never boring. Adding a glass container, however small, will add a quirky feature to your collection. And with these useful tips, you will have a fantastic planted indoor terrarium to display in your home.